THE REAL LOLITA: The Kidnapping of Sally Horner and the Novel That Scandalized the World, by Sarah Weinman. Ecco, 306 pp., $27.99.

“I first read 'Lolita' at sixteen, as a high school junior whose intellectual curiosity far exceeded her emotional maturity,” writes Sarah Weinman. “I thought I could handle what transpired between Dolores Haze and Humbert Humbert. I thought I could appreciate the language and not be affected by the story. I pretended I was ready for 'Lolita,' but I was nowhere close.”

She’s ready now. As a writer, editor and critic, Weinman has focused for years on the intersection of crime and gender, often set in the landscape of midcentury America (her previous projects include the Library of America boxed set of women crime writers of the 1940s and '50s). In “The Real Lolita,” Weinman has expanded upon a story she began as a magazine article about a mostly forgotten crime — the kidnapping of a New Jersey girl in 1948 — and its influence on Vladimir Nabokov’s most famous novel.

Sally Horner was 11 when she boarded a bus in Camden, New Jersey, with Frank La Salle, a middle-age man who claimed to be an FBI agent. He’d seen her shoplift from a local store months earlier and said he’d let her get away with that crime if she became his informant. She had to come with him to Atlantic City, he told her; he told Sally’s mother that he and his wife were the parents of one of Sally’s friends and wanted her to join them for a vacation that she couldn’t afford to give her daughter. Sally’s mother agreed; she wouldn’t see her daughter again for 20 months.

Her abduction was news, but her return after nearly two years — time spent pretending to be La Salle’s daughter, traveling with him from New Jersey to Baltimore to Dallas and finally to San Jose, where a suspicious neighbor learned the truth and helped Sally alert the authorities — was a sensation. The newspapers printed a photograph of Sally re-creating her first telephone call home, a beautiful girl just about to turn 13. Although Weinman writes that “there is no direct proof that Vladimir Nabokov learned of Sally Horner’s abduction and rescue in March 1950,” it’s easy to see how the novelist, laid up in bed much of that spring, struggling to get a handle on a writing project, would seize upon the true crime story in front of him.

Nabokov mentions Sally Horner and Frank La Salle in “Lolita,” in one of Humbert’s frequent flirtations with accepting responsibility for his pedophilia, but the writer — through his wife, the formidable Véra — rejected the notion that his novel was based on her story, or anyone’s. It’s true, Weinman points out, that Nabokov had written before about a middle-age man lusting for a girl in a novella titled “The Enchanter.” The project of trying to deduce where a work of fiction comes from, beyond its author’s own mind, is generally a pointless one — which is why, I imagine, Weinman so deftly sidesteps any such claim. Instead, she argues that Nabokov likely found in Sally’s story a useful template that helped him complete “Lolita” (in which his fictional girl returns from captivity to a mundane and early death, just as Sally did in real life).

Ultimately, though, Weinman’s project is less about Nabokov (and Humbert) than it is about Sally (and Lolita). The book is riveting — a lively blend of literary research and crime reporting, but what makes it so haunting is Weinman’s own moral center of gravity. “Knowing about Sally Horner does not diminish 'Lolita’'s brilliance, or Nabokov’s audacious inventiveness,” she writes, “but it does augment the horror he also captured in the novel.”